<?php
namespace Dwoo\Plugins\Blocks;
use Dwoo\Block\Plugin;
use Dwoo\Compiler;
use Dwoo\ICompilable\Block;
use Dwoo\IElseable;

/**
 * Similar to the php for block
 * <pre>
 *  * name : for name to access it's iterator variables through {$.for.name.var} see {@link http://wiki.dwoo.org/index.php/IteratorVariables} for details
 *  * from : array to iterate from (which equals 0) or a number as a start value
 *  * to : value to stop iterating at (equals count($array) by default if you set an array in from)
 *  * step : defines the incrementation of the pointer at each iteration
 * </pre>
 * This software is provided 'as-is', without any express or implied warranty.
 * In no event will the authors be held liable for any damages arising from the use of this software.
 *
 * @author     Jordi Boggiano <j.boggiano@seld.be>
 * @copyright  Copyright (c) 2008, Jordi Boggiano
 * @license    http://dwoo.org/LICENSE   Modified BSD License
 * @link       http://dwoo.org/
 * @version    2.0
 * @date       2013-09-06
 * @package    Dwoo
 */
class BlockFor extends Plugin implements Block, IElseable {
	public static $cnt = 0;

	public function begin($name, $from, $to = null, $step = 1, $skip = 0) {

	}

	public static function preProcessing(Compiler $compiler, array $params, $prepend, $append, $type) {
		// get block params and save the current template pointer to use it in the postProcessing method
		$currentBlock                         =& $compiler->getCurrentBlock();
		$currentBlock['params']['tplPointer'] = $compiler->getPointer();

		return '';
	}

	public static function postProcessing(Compiler $compiler, array $params, $prepend, $append, $content) {
		$params = $compiler->getCompiledParams($params);
		$tpl    = $compiler->getTemplateSource($params['tplPointer']);

		// assigns params
		$from = $params['from'];
		$name = $params['name'];
		$step = $params['step'];
		$to   = $params['to'];

		// evaluates which global variables have to be computed
		$varName       = '$dwoo.for.' . trim($name, '"\'') . '.';
		$shortVarName  = '$.for.' . trim($name, '"\'') . '.';
		$usesAny       = strpos($tpl, $varName) !== false || strpos($tpl, $shortVarName) !== false;
		$usesFirst     = strpos($tpl, $varName . 'first') !== false || strpos($tpl, $shortVarName . 'first') !== false;
		$usesLast      = strpos($tpl, $varName . 'last') !== false || strpos($tpl, $shortVarName . 'last') !== false;
		$usesIndex     = strpos($tpl, $varName . 'index') !== false || strpos($tpl, $shortVarName . 'index') !== false;
		$usesIteration = $usesFirst || $usesLast || strpos($tpl, $varName . 'iteration') !== false || strpos($tpl, $shortVarName . 'iteration') !== false;
		$usesShow      = strpos($tpl, $varName . 'show') !== false || strpos($tpl, $shortVarName . 'show') !== false;
		$usesTotal     = $usesLast || strpos($tpl, $varName . 'total') !== false || strpos($tpl, $shortVarName . 'total') !== false;

		if (strpos($name, '$this->scope[') !== false) {
			$usesAny = $usesFirst = $usesLast = $usesIndex = $usesIteration = $usesShow = $usesTotal = true;
		}

		// gets foreach id
		$cnt = self::$cnt ++;

		// builds pre processing output for
		$out = Compiler::PHP_OPEN . "\n" . '$_for' . $cnt . '_from = ' . $from . ';' .
			"\n" . '$_for' . $cnt . '_to = ' . $to . ';' .
			"\n" . '$_for' . $cnt . '_step = abs(' . $step . ');' .
			"\n" . 'if (is_numeric($_for' . $cnt . '_from) && !is_numeric($_for' . $cnt . '_to)) { $this->triggerError(\'For requires the <em>to</em> parameter when using a numerical <em>from</em>\'); }' .
			"\n" . '$tmp_shows = $this->isArray($_for' . $cnt . '_from, true) || (is_numeric($_for' . $cnt . '_from) && (abs(($_for' . $cnt . '_from - $_for' . $cnt . '_to)/$_for' . $cnt . '_step) !== 0 || $_for' . $cnt . '_from == $_for' . $cnt . '_to));';
		// adds for properties
		if ($usesAny) {
			$out .= "\n" . '$this->globals["for"][' . $name . '] = array' . "\n(";
			if ($usesIndex) {
				$out .= "\n\t" . '"index"		=> 0,';
			}
			if ($usesIteration) {
				$out .= "\n\t" . '"iteration"		=> 1,';
			}
			if ($usesFirst) {
				$out .= "\n\t" . '"first"		=> null,';
			}
			if ($usesLast) {
				$out .= "\n\t" . '"last"		=> null,';
			}
			if ($usesShow) {
				$out .= "\n\t" . '"show"		=> $tmp_shows,';
			}
			if ($usesTotal) {
				$out .= "\n\t" . '"total"		=> $this->isArray($_for' . $cnt . '_from) ? floor($this->count($_for' . $cnt . '_from) / $_for' . $cnt . '_step) : (is_numeric($_for' . $cnt . '_from) ? abs(($_for' . $cnt . '_to + 1 - $_for' . $cnt . '_from)/$_for' . $cnt . '_step) : 0),';
			}
			$out .= "\n);\n" . '$_for' . $cnt . '_glob =& $this->globals["for"][' . $name . '];';
		}
		// checks if for must be looped
		$out .= "\n" . 'if ($tmp_shows)' . "\n{";
		// set from/to to correct values if an array was given
		$out .= "\n\t" . 'if ($this->isArray($_for' . $cnt . '_from' . (isset($params['hasElse']) ? ', true' : '') . ') == true) {
		$_for' . $cnt . '_to = is_numeric($_for' . $cnt . '_to) ? $_for' . $cnt . '_to - $_for' . $cnt . '_step : $this->count($_for' . $cnt . '_from) - 1;
		$_for' . $cnt . '_from = 0;
	}';

		// if input are pure numbers it shouldn't reorder them, if it's variables it gets too messy though so in that case a counter should be used
		$reverse     = false;
		$condition   = '<=';
		$incrementer = '+';

		if (preg_match('{^(["\']?)([0-9]+)\1$}', $from, $mN1) && preg_match('{^(["\']?)([0-9]+)\1$}', $to, $mN2)) {
			$from = (int)$mN1[2];
			$to   = (int)$mN2[2];
			if ($from > $to) {
				$reverse     = true;
				$condition   = '>=';
				$incrementer = '-';
			}
		}

		// reverse from and to if needed
		if (! $reverse) {
			$out .= "\n\t" . 'if ($_for' . $cnt . '_from > $_for' . $cnt . '_to) {
				$tmp = $_for' . $cnt . '_from;
				$_for' . $cnt . '_from = $_for' . $cnt . '_to;
				$_for' . $cnt . '_to = $tmp;
			}';
		}

		$out .= "\n\t" . 'for ($this->scope[' . $name . '] = $_for' . $cnt . '_from; $this->scope[' . $name . '] ' . $condition . ' $_for' . $cnt . '_to; $this->scope[' . $name . '] ' . $incrementer . '= $_for' . $cnt . '_step)' . "\n\t{";
		// updates properties
		if ($usesIndex) {
			$out .= "\n\t\t" . '$_for' . $cnt . '_glob["index"] = $this->scope[' . $name . '];';
		}
		if ($usesFirst) {
			$out .= "\n\t\t" . '$_for' . $cnt . '_glob["first"] = (string) ($_for' . $cnt . '_glob["iteration"] === 1);';
		}
		if ($usesLast) {
			$out .= "\n\t\t" . '$_for' . $cnt . '_glob["last"] = (string) ($_for' . $cnt . '_glob["iteration"] === $_for' . $cnt . '_glob["total"]);';
		}
		$out .= "\n/* -- for start output */\n" . Compiler::PHP_CLOSE;

		// build post processing output and cache it
		$postOut = Compiler::PHP_OPEN . '/* -- for end output */';
		// update properties
		if ($usesIteration) {
			$postOut .= "\n\t\t" . '$_for' . $cnt . '_glob["iteration"]+=1;';
		}
		// end loop
		$postOut .= "\n\t}\n}\n" . Compiler::PHP_CLOSE;

		if (isset($params['hasElse'])) {
			$postOut .= $params['hasElse'];
		}

		return $out . $content . $postOut;
	}
}
